This invention pertains to battery jumper cables and, more particularly, to battery jumper cables that utilize a fail-safe positive lockout to prevent incorrect use of the jumper cables.
Jumper cables for use in starting an automobile vehicle having a discharged battery with another vehicle having a charged battery are well known devices.
In the past, jumper cables have generally been constructed of two continuous lengths of insulated wire of suitable gauge which are terminated at their ends with clamps. In use the cables are attached to the charged and discharged batteries to form a circuit to enable the charged battery (commonly referred to as the good battery) to provide the ignition current and voltage for the discharged battery (commonly referred to as the dead battery). Through the use of jumper cables, sometimes referred to as booster cables, a vehicle with a dead battery can be started using a good battery.
There are many risks associated with the use of jumper cables. Automotive batteries and ignition systems involve very high currents and, as a consequence, there exists a danger of electric shock and burns from incorrectly attaching the jumper cables to the battery terminals. Incorrect attachment can also cause the batteries to explode resulting in battery acid burns and other injuries. Additionally, the sparks which can result from connecting the jumper cable clamps to the batteries can ignite hydrogen gas in the vicinity of the batteries causing fire and/or explosion. The dangers and risks involved in using jumper cables are enhanced by the circumstances under which jumper cables are usually used. Although the clamps of the cables may be properly color-coded, proper identification of the negative and positive terminals is made difficult in poorly lit environments with poorly marked battery terminals that have become obscured by age, dirt and grime.
Enhancements to jumper cables have been proposed in order to aid in correctly attaching the cables to the batteries by utilizing lights and a remote connection point. One such jumper cable is shown in U.S. Pat. No. 4,272,142 to Zapf. However, in general such prior improvements do not positively prevent incorrect connection of the batteries.
Accordingly it is desirable to provide a safety jumper cable that utilizes a fail-safe positive lockout to prevent incorrect connection of the batteries.